| from typing import Any, Dict, List, Optional, Union, cast |
|
|
| from fastapi.exceptions import HTTPException |
| from fastapi.openapi.models import OAuth2 as OAuth2Model |
| from fastapi.openapi.models import OAuthFlows as OAuthFlowsModel |
| from fastapi.param_functions import Form |
| from fastapi.security.base import SecurityBase |
| from fastapi.security.utils import get_authorization_scheme_param |
| from starlette.requests import Request |
| from starlette.status import HTTP_401_UNAUTHORIZED, HTTP_403_FORBIDDEN |
|
|
| |
| from typing_extensions import Annotated, Doc |
|
|
|
|
| class OAuth2PasswordRequestForm: |
| """ |
| This is a dependency class to collect the `username` and `password` as form data |
| for an OAuth2 password flow. |
| |
| The OAuth2 specification dictates that for a password flow the data should be |
| collected using form data (instead of JSON) and that it should have the specific |
| fields `username` and `password`. |
| |
| All the initialization parameters are extracted from the request. |
| |
| Read more about it in the |
| [FastAPI docs for Simple OAuth2 with Password and Bearer](https://fastapi.tiangolo.com/tutorial/security/simple-oauth2/). |
| |
| ## Example |
| |
| ```python |
| from typing import Annotated |
| |
| from fastapi import Depends, FastAPI |
| from fastapi.security import OAuth2PasswordRequestForm |
| |
| app = FastAPI() |
| |
| |
| @app.post("/login") |
| def login(form_data: Annotated[OAuth2PasswordRequestForm, Depends()]): |
| data = {} |
| data["scopes"] = [] |
| for scope in form_data.scopes: |
| data["scopes"].append(scope) |
| if form_data.client_id: |
| data["client_id"] = form_data.client_id |
| if form_data.client_secret: |
| data["client_secret"] = form_data.client_secret |
| return data |
| ``` |
| |
| Note that for OAuth2 the scope `items:read` is a single scope in an opaque string. |
| You could have custom internal logic to separate it by colon caracters (`:`) or |
| similar, and get the two parts `items` and `read`. Many applications do that to |
| group and organize permissions, you could do it as well in your application, just |
| know that that it is application specific, it's not part of the specification. |
| """ |
|
|
| def __init__( |
| self, |
| *, |
| grant_type: Annotated[ |
| Union[str, None], |
| Form(pattern="password"), |
| Doc( |
| """ |
| The OAuth2 spec says it is required and MUST be the fixed string |
| "password". Nevertheless, this dependency class is permissive and |
| allows not passing it. If you want to enforce it, use instead the |
| `OAuth2PasswordRequestFormStrict` dependency. |
| """ |
| ), |
| ] = None, |
| username: Annotated[ |
| str, |
| Form(), |
| Doc( |
| """ |
| `username` string. The OAuth2 spec requires the exact field name |
| `username`. |
| """ |
| ), |
| ], |
| password: Annotated[ |
| str, |
| Form(), |
| Doc( |
| """ |
| `password` string. The OAuth2 spec requires the exact field name |
| `password". |
| """ |
| ), |
| ], |
| scope: Annotated[ |
| str, |
| Form(), |
| Doc( |
| """ |
| A single string with actually several scopes separated by spaces. Each |
| scope is also a string. |
| |
| For example, a single string with: |
| |
| ```python |
| "items:read items:write users:read profile openid" |
| ```` |
| |
| would represent the scopes: |
| |
| * `items:read` |
| * `items:write` |
| * `users:read` |
| * `profile` |
| * `openid` |
| """ |
| ), |
| ] = "", |
| client_id: Annotated[ |
| Union[str, None], |
| Form(), |
| Doc( |
| """ |
| If there's a `client_id`, it can be sent as part of the form fields. |
| But the OAuth2 specification recommends sending the `client_id` and |
| `client_secret` (if any) using HTTP Basic auth. |
| """ |
| ), |
| ] = None, |
| client_secret: Annotated[ |
| Union[str, None], |
| Form(), |
| Doc( |
| """ |
| If there's a `client_password` (and a `client_id`), they can be sent |
| as part of the form fields. But the OAuth2 specification recommends |
| sending the `client_id` and `client_secret` (if any) using HTTP Basic |
| auth. |
| """ |
| ), |
| ] = None, |
| ): |
| self.grant_type = grant_type |
| self.username = username |
| self.password = password |
| self.scopes = scope.split() |
| self.client_id = client_id |
| self.client_secret = client_secret |
|
|
|
|
| class OAuth2PasswordRequestFormStrict(OAuth2PasswordRequestForm): |
| """ |
| This is a dependency class to collect the `username` and `password` as form data |
| for an OAuth2 password flow. |
| |
| The OAuth2 specification dictates that for a password flow the data should be |
| collected using form data (instead of JSON) and that it should have the specific |
| fields `username` and `password`. |
| |
| All the initialization parameters are extracted from the request. |
| |
| The only difference between `OAuth2PasswordRequestFormStrict` and |
| `OAuth2PasswordRequestForm` is that `OAuth2PasswordRequestFormStrict` requires the |
| client to send the form field `grant_type` with the value `"password"`, which |
| is required in the OAuth2 specification (it seems that for no particular reason), |
| while for `OAuth2PasswordRequestForm` `grant_type` is optional. |
| |
| Read more about it in the |
| [FastAPI docs for Simple OAuth2 with Password and Bearer](https://fastapi.tiangolo.com/tutorial/security/simple-oauth2/). |
| |
| ## Example |
| |
| ```python |
| from typing import Annotated |
| |
| from fastapi import Depends, FastAPI |
| from fastapi.security import OAuth2PasswordRequestForm |
| |
| app = FastAPI() |
| |
| |
| @app.post("/login") |
| def login(form_data: Annotated[OAuth2PasswordRequestFormStrict, Depends()]): |
| data = {} |
| data["scopes"] = [] |
| for scope in form_data.scopes: |
| data["scopes"].append(scope) |
| if form_data.client_id: |
| data["client_id"] = form_data.client_id |
| if form_data.client_secret: |
| data["client_secret"] = form_data.client_secret |
| return data |
| ``` |
| |
| Note that for OAuth2 the scope `items:read` is a single scope in an opaque string. |
| You could have custom internal logic to separate it by colon caracters (`:`) or |
| similar, and get the two parts `items` and `read`. Many applications do that to |
| group and organize permissions, you could do it as well in your application, just |
| know that that it is application specific, it's not part of the specification. |
| |
| |
| grant_type: the OAuth2 spec says it is required and MUST be the fixed string "password". |
| This dependency is strict about it. If you want to be permissive, use instead the |
| OAuth2PasswordRequestForm dependency class. |
| username: username string. The OAuth2 spec requires the exact field name "username". |
| password: password string. The OAuth2 spec requires the exact field name "password". |
| scope: Optional string. Several scopes (each one a string) separated by spaces. E.g. |
| "items:read items:write users:read profile openid" |
| client_id: optional string. OAuth2 recommends sending the client_id and client_secret (if any) |
| using HTTP Basic auth, as: client_id:client_secret |
| client_secret: optional string. OAuth2 recommends sending the client_id and client_secret (if any) |
| using HTTP Basic auth, as: client_id:client_secret |
| """ |
|
|
| def __init__( |
| self, |
| grant_type: Annotated[ |
| str, |
| Form(pattern="password"), |
| Doc( |
| """ |
| The OAuth2 spec says it is required and MUST be the fixed string |
| "password". This dependency is strict about it. If you want to be |
| permissive, use instead the `OAuth2PasswordRequestForm` dependency |
| class. |
| """ |
| ), |
| ], |
| username: Annotated[ |
| str, |
| Form(), |
| Doc( |
| """ |
| `username` string. The OAuth2 spec requires the exact field name |
| `username`. |
| """ |
| ), |
| ], |
| password: Annotated[ |
| str, |
| Form(), |
| Doc( |
| """ |
| `password` string. The OAuth2 spec requires the exact field name |
| `password". |
| """ |
| ), |
| ], |
| scope: Annotated[ |
| str, |
| Form(), |
| Doc( |
| """ |
| A single string with actually several scopes separated by spaces. Each |
| scope is also a string. |
| |
| For example, a single string with: |
| |
| ```python |
| "items:read items:write users:read profile openid" |
| ```` |
| |
| would represent the scopes: |
| |
| * `items:read` |
| * `items:write` |
| * `users:read` |
| * `profile` |
| * `openid` |
| """ |
| ), |
| ] = "", |
| client_id: Annotated[ |
| Union[str, None], |
| Form(), |
| Doc( |
| """ |
| If there's a `client_id`, it can be sent as part of the form fields. |
| But the OAuth2 specification recommends sending the `client_id` and |
| `client_secret` (if any) using HTTP Basic auth. |
| """ |
| ), |
| ] = None, |
| client_secret: Annotated[ |
| Union[str, None], |
| Form(), |
| Doc( |
| """ |
| If there's a `client_password` (and a `client_id`), they can be sent |
| as part of the form fields. But the OAuth2 specification recommends |
| sending the `client_id` and `client_secret` (if any) using HTTP Basic |
| auth. |
| """ |
| ), |
| ] = None, |
| ): |
| super().__init__( |
| grant_type=grant_type, |
| username=username, |
| password=password, |
| scope=scope, |
| client_id=client_id, |
| client_secret=client_secret, |
| ) |
|
|
|
|
| class OAuth2(SecurityBase): |
| """ |
| This is the base class for OAuth2 authentication, an instance of it would be used |
| as a dependency. All other OAuth2 classes inherit from it and customize it for |
| each OAuth2 flow. |
| |
| You normally would not create a new class inheriting from it but use one of the |
| existing subclasses, and maybe compose them if you want to support multiple flows. |
| |
| Read more about it in the |
| [FastAPI docs for Security](https://fastapi.tiangolo.com/tutorial/security/). |
| """ |
|
|
| def __init__( |
| self, |
| *, |
| flows: Annotated[ |
| Union[OAuthFlowsModel, Dict[str, Dict[str, Any]]], |
| Doc( |
| """ |
| The dictionary of OAuth2 flows. |
| """ |
| ), |
| ] = OAuthFlowsModel(), |
| scheme_name: Annotated[ |
| Optional[str], |
| Doc( |
| """ |
| Security scheme name. |
| |
| It will be included in the generated OpenAPI (e.g. visible at `/docs`). |
| """ |
| ), |
| ] = None, |
| description: Annotated[ |
| Optional[str], |
| Doc( |
| """ |
| Security scheme description. |
| |
| It will be included in the generated OpenAPI (e.g. visible at `/docs`). |
| """ |
| ), |
| ] = None, |
| auto_error: Annotated[ |
| bool, |
| Doc( |
| """ |
| By default, if no HTTP Authorization header is provided, required for |
| OAuth2 authentication, it will automatically cancel the request and |
| send the client an error. |
| |
| If `auto_error` is set to `False`, when the HTTP Authorization header |
| is not available, instead of erroring out, the dependency result will |
| be `None`. |
| |
| This is useful when you want to have optional authentication. |
| |
| It is also useful when you want to have authentication that can be |
| provided in one of multiple optional ways (for example, with OAuth2 |
| or in a cookie). |
| """ |
| ), |
| ] = True, |
| ): |
| self.model = OAuth2Model( |
| flows=cast(OAuthFlowsModel, flows), description=description |
| ) |
| self.scheme_name = scheme_name or self.__class__.__name__ |
| self.auto_error = auto_error |
|
|
| async def __call__(self, request: Request) -> Optional[str]: |
| authorization = request.headers.get("Authorization") |
| if not authorization: |
| if self.auto_error: |
| raise HTTPException( |
| status_code=HTTP_403_FORBIDDEN, detail="Not authenticated" |
| ) |
| else: |
| return None |
| return authorization |
|
|
|
|
| class OAuth2PasswordBearer(OAuth2): |
| """ |
| OAuth2 flow for authentication using a bearer token obtained with a password. |
| An instance of it would be used as a dependency. |
| |
| Read more about it in the |
| [FastAPI docs for Simple OAuth2 with Password and Bearer](https://fastapi.tiangolo.com/tutorial/security/simple-oauth2/). |
| """ |
|
|
| def __init__( |
| self, |
| tokenUrl: Annotated[ |
| str, |
| Doc( |
| """ |
| The URL to obtain the OAuth2 token. This would be the *path operation* |
| that has `OAuth2PasswordRequestForm` as a dependency. |
| """ |
| ), |
| ], |
| scheme_name: Annotated[ |
| Optional[str], |
| Doc( |
| """ |
| Security scheme name. |
| |
| It will be included in the generated OpenAPI (e.g. visible at `/docs`). |
| """ |
| ), |
| ] = None, |
| scopes: Annotated[ |
| Optional[Dict[str, str]], |
| Doc( |
| """ |
| The OAuth2 scopes that would be required by the *path operations* that |
| use this dependency. |
| """ |
| ), |
| ] = None, |
| description: Annotated[ |
| Optional[str], |
| Doc( |
| """ |
| Security scheme description. |
| |
| It will be included in the generated OpenAPI (e.g. visible at `/docs`). |
| """ |
| ), |
| ] = None, |
| auto_error: Annotated[ |
| bool, |
| Doc( |
| """ |
| By default, if no HTTP Authorization header is provided, required for |
| OAuth2 authentication, it will automatically cancel the request and |
| send the client an error. |
| |
| If `auto_error` is set to `False`, when the HTTP Authorization header |
| is not available, instead of erroring out, the dependency result will |
| be `None`. |
| |
| This is useful when you want to have optional authentication. |
| |
| It is also useful when you want to have authentication that can be |
| provided in one of multiple optional ways (for example, with OAuth2 |
| or in a cookie). |
| """ |
| ), |
| ] = True, |
| ): |
| if not scopes: |
| scopes = {} |
| flows = OAuthFlowsModel( |
| password=cast(Any, {"tokenUrl": tokenUrl, "scopes": scopes}) |
| ) |
| super().__init__( |
| flows=flows, |
| scheme_name=scheme_name, |
| description=description, |
| auto_error=auto_error, |
| ) |
|
|
| async def __call__(self, request: Request) -> Optional[str]: |
| authorization = request.headers.get("Authorization") |
| scheme, param = get_authorization_scheme_param(authorization) |
| if not authorization or scheme.lower() != "bearer": |
| if self.auto_error: |
| raise HTTPException( |
| status_code=HTTP_401_UNAUTHORIZED, |
| detail="Not authenticated", |
| headers={"WWW-Authenticate": "Bearer"}, |
| ) |
| else: |
| return None |
| return param |
|
|
|
|
| class OAuth2AuthorizationCodeBearer(OAuth2): |
| """ |
| OAuth2 flow for authentication using a bearer token obtained with an OAuth2 code |
| flow. An instance of it would be used as a dependency. |
| """ |
|
|
| def __init__( |
| self, |
| authorizationUrl: str, |
| tokenUrl: Annotated[ |
| str, |
| Doc( |
| """ |
| The URL to obtain the OAuth2 token. |
| """ |
| ), |
| ], |
| refreshUrl: Annotated[ |
| Optional[str], |
| Doc( |
| """ |
| The URL to refresh the token and obtain a new one. |
| """ |
| ), |
| ] = None, |
| scheme_name: Annotated[ |
| Optional[str], |
| Doc( |
| """ |
| Security scheme name. |
| |
| It will be included in the generated OpenAPI (e.g. visible at `/docs`). |
| """ |
| ), |
| ] = None, |
| scopes: Annotated[ |
| Optional[Dict[str, str]], |
| Doc( |
| """ |
| The OAuth2 scopes that would be required by the *path operations* that |
| use this dependency. |
| """ |
| ), |
| ] = None, |
| description: Annotated[ |
| Optional[str], |
| Doc( |
| """ |
| Security scheme description. |
| |
| It will be included in the generated OpenAPI (e.g. visible at `/docs`). |
| """ |
| ), |
| ] = None, |
| auto_error: Annotated[ |
| bool, |
| Doc( |
| """ |
| By default, if no HTTP Authorization header is provided, required for |
| OAuth2 authentication, it will automatically cancel the request and |
| send the client an error. |
| |
| If `auto_error` is set to `False`, when the HTTP Authorization header |
| is not available, instead of erroring out, the dependency result will |
| be `None`. |
| |
| This is useful when you want to have optional authentication. |
| |
| It is also useful when you want to have authentication that can be |
| provided in one of multiple optional ways (for example, with OAuth2 |
| or in a cookie). |
| """ |
| ), |
| ] = True, |
| ): |
| if not scopes: |
| scopes = {} |
| flows = OAuthFlowsModel( |
| authorizationCode=cast( |
| Any, |
| { |
| "authorizationUrl": authorizationUrl, |
| "tokenUrl": tokenUrl, |
| "refreshUrl": refreshUrl, |
| "scopes": scopes, |
| }, |
| ) |
| ) |
| super().__init__( |
| flows=flows, |
| scheme_name=scheme_name, |
| description=description, |
| auto_error=auto_error, |
| ) |
|
|
| async def __call__(self, request: Request) -> Optional[str]: |
| authorization = request.headers.get("Authorization") |
| scheme, param = get_authorization_scheme_param(authorization) |
| if not authorization or scheme.lower() != "bearer": |
| if self.auto_error: |
| raise HTTPException( |
| status_code=HTTP_401_UNAUTHORIZED, |
| detail="Not authenticated", |
| headers={"WWW-Authenticate": "Bearer"}, |
| ) |
| else: |
| return None |
| return param |
|
|
|
|
| class SecurityScopes: |
| """ |
| This is a special class that you can define in a parameter in a dependency to |
| obtain the OAuth2 scopes required by all the dependencies in the same chain. |
| |
| This way, multiple dependencies can have different scopes, even when used in the |
| same *path operation*. And with this, you can access all the scopes required in |
| all those dependencies in a single place. |
| |
| Read more about it in the |
| [FastAPI docs for OAuth2 scopes](https://fastapi.tiangolo.com/advanced/security/oauth2-scopes/). |
| """ |
|
|
| def __init__( |
| self, |
| scopes: Annotated[ |
| Optional[List[str]], |
| Doc( |
| """ |
| This will be filled by FastAPI. |
| """ |
| ), |
| ] = None, |
| ): |
| self.scopes: Annotated[ |
| List[str], |
| Doc( |
| """ |
| The list of all the scopes required by dependencies. |
| """ |
| ), |
| ] = scopes or [] |
| self.scope_str: Annotated[ |
| str, |
| Doc( |
| """ |
| All the scopes required by all the dependencies in a single string |
| separated by spaces, as defined in the OAuth2 specification. |
| """ |
| ), |
| ] = " ".join(self.scopes) |
|
|
